As mentioned previously, we have too much stuff. Some of it must go before we move.
After putting it off for weeks, I've eventually started on my books. Inspired by an item in the Guardina supplement about free stuff, I have spent several hours adding my unwanted books to Read It Swap It, which as its name suggests is a book swapping service. I realise this won't actually decrease the number of books I have as I will receive a book in return, but it will at least provide me with something new to read and mean that my books will be moving so not just gathering dust.
I've no idea how successful it will be, but it has motivated me into at least sorting my books into those I want to keep and those I don't. If it shows no sign of bearing fruit by the time we move, I will revert to Plan A of donating the books to the library or Plan B a charity shop.